BUENOS AIRES — President Barack Obama expressed regret Thursday for the failure of the United States to acknowledge the brutal repression and atrocities that took place during Argentina's "dirty war" in the 1970s and '80s.

"There's been controversy about the policies of the United States early in those dark days," Obama said at the Parque de la Memoria, a monument to the war's victims, where he attended a ceremony for the 40th anniversary of the 1976 military coup that began the Argentine dictatorship.

The United States "has to examine its own policies as well, and its own past," Obama added. "We've been slow to speak out for human rights, and that was the case here."

The president's remarks came after he toured the memorial with President Mauricio Macri of Argentina, walking beside a hulking gray stone wall engraved with the names and ages of 20,000 victims — plus 10,000 blank spaces for those who have yet to be identified.

Obama announced this week that he would begin a declassification effort to unseal secret military and intelligence files that could shed light on the fates of some of those victims, as well as what the United States knew about the human rights violations that took place during what Macri called "the darkest period in our history."

The leaders walked together to a bridgehead overlooking the Río de la Plata, where they each cast three white roses into the water to honor the victims.

"A memorial like this speaks to the responsibilities that all of us have," Obama said later. "We cannot forget the past, but when we find the courage to confront and we find the courage to change that past, that's when we build a better future."

Human rights groups had reacted angrily to the timing of Obama's trip, arguing that it was inappropriate for him to visit at the very moment that Argentina was commemorating a tragic turn in its history that many believe was condoned, and in some cases enabled, by the United States.

Macri thanked Obama for participating in Argentina's somber day of remembrance, and said nations must not be "passive onlookers" of human rights violations, as had been the case in the past.

"This is a marvelous opportunity for all of the Argentine people to say together, 'Never again,'" Macri said. "Never again to institutional violence."

Obama and his family then departed to tour Argentina's scenic Patagonia region. He was being kept abreast of the investigation into the Brussels attacks by his national security staff back in Washington.

Lisa Monaco, his top counterterrorism adviser, briefed Obama by secure phone call Thursday morning, a White House official said. The president has directed his team to "continue providing any and all requested assistance to Belgian and other authorities investigating the attacks," the official said.

The White House said Thursday that Obama will meet with President Xi Jinping of China next week on the sidelines of a nuclear security meeting in Washington.

The two leaders, who last met in September, will discuss how they can work together on "issues of mutual interest," and also to "address areas of disagreement constructively," the White House said in a statement.

PUNGGYE-RI, North Korea — North Korean leader Kim Jong Un made good on his promise to demolish his country’s nuclear test site, which was formally closed in a series of huge explosions Thursday as a group of foreign journalists looked on. The explosi...

President Donald Trump’s decision to block his Twitter followers for their political views is a violation of the First Amendment, a federal judge ruled Wednesday, saying that Trump’s effort to silence his critics is not permissible under the U.S. Con...

TAMPA — All those public watch parties during the Tampa Bay Lightning’s postseason run? And how about the rally at Joe Chillura Courthouse Square Park with the big white Lightning logo spray-painted on the grass?
You need police to prote...

Explain this to me:
In the world of partisan politics, how is being an independent thinker a bad thing?
When it comes to general elections, we seem to like rogues and mavericks. We want outsiders and swamp scrubbers. Folks appreciate a good finger-...

WASHINGTON - President Donald Trump lashed out Sunday at "the World’s most expensive Witch Hunt," trashing a new report in the New York Times that said an emissary representing the governments of Saudi Arabia and the United Arab Emirates offered help...

Former Education Secretary Arne Duncan pushed a radical idea on Twitter: Parents should pull their children out of school until elected officials pass stricter gun control laws.His tweet came hours after a shooting rampage at a Houston-area high scho...

WASHINGTON - China offered to boost its annual purchases of U.S. products by "at least $200 billion" Friday as two days of talks aimed at averting an open breach between the two countries ended in Washington, a top White House adviser said.Larry Kudl...

TAMPA — A concert organizer is accusing Hillsborough County Commission candidate Elvis Piggott of falsifying a contract and prompting the headline act to pull out of a gospel show.In a lawsuit filed in Hillsborough Circuit Court, Corey Curry claims h...

WASHINGTON - The Senate voted Thursday to confirm Gina Haspel as the next CIA director after several Democrats were persuaded to support her despite lingering concerns about her role in the brutal interrogation of suspected terrorists captured after ...

WASHINGTON — Republicans are pushing for a speedy confirmation vote as early as Thursday after the Senate intelligence committee endorsed President Donald Trump’s CIA nominee Gina Haspel to lead the spy agency. But opponents concerned about Haspel’s ...